Answer is: <span>negative beta decay.
</span>
Nuclear reaction: ¹⁴C → ¹⁴N + e⁻ + νe (electron antineutrino).
<span>In beta minus decay (atomic number Z is increased
by one, from 6 in carbon to 7 in nitrogen) neutron is converted to a proton and
an electron and an electron antineutrino.
</span><span>Beta decay is radioactive decay in which a beta
ray and a neutrino are emitted from an atomic nucleus.</span>
Because there no choices there, most probably it should be about hydrogen bonding in the water, which is the most important intermolecular force in water.
Primary alkyl halides tend to undergo the SN2 reaction mechanism in nucleophilic substitution since there is less steric hindrance for nucleophilic attack and the carbocations that they form are not as stable as those formed from tertiary alkyl halides.
1-bromopentane > 1-bromo 2-methylbutane > <span>1-bromo-3-methylbutane</span>> 2-bromo 2-methylbutane
Answer:
The standard enthalpy of formation of HgO is -90.7 kJ/mol.
Explanation:
The reaction between Hg and oxygen is as follows.

From the given,
Molar mass of HgO = 216.59 g/mol
Mass of HgO decomposed = 18.5 g
Amount of heat absorbed = 7.75 kJ
From the reaction,
The standard enthalpy of formation = 
During the decomposition of 1 mol of HgO , 90.7 kJ of energy absorbed.
For the formation of 1 mol of HgO , 90.7 kJ of energy is release
Therefore, the enthalpy of formation of mercury(II)Oxide is -90.7 kJ/mol